Tony Buffa, a veteran Lake Ontario charter boat captain who operates out of Oswego Marina, was understandably excited Sunday. He thought he might have a world record on his hands.

It was 7 a.m. Sunday and one of his clients, Johnnie Rudisil, 30, of Bethel, Conn., had just reeled in a 35-pound, 1-ounce coho salmon. Rudisil was fishing on Buffa's boat with his grandfather, Tony Mallozzi, also of Connecticut.

The world-record coho weighed 33 pounds, 7 ounces and was caught by Stephen Sheets Jr. on Lake Ontario, fishing out of Oswego County, on July 13, 1998.

Buffa was not taking any chances. He had the fish weighed on a scale used for tournaments at Larry’s Salmon Shop in Oswego. The fish was put on ice overnight and Rudisil drove it to the regional DEC office in Cortland on Monday for analysis.

The DEC’s conclusion?

“Potentially, he (Buffa) was right,” said Dan Bishop, regional supervisor for natural resources at the Cortland office. “But we checked it out, and it does not appear to be the case.”

The reason, Bishop said, was that the fish was actually a hybrid — a cross between a coho and its larger cousin, a chinook (king) salmon. That was determined, Bishop said, by cutting a small slice in the fish’s belly and pulling out its pyloric caeca — finger-shaped pouches located where the intestine and the stomach meet.

Bishop said the number of pyloric caeca ranges from 53 to 80 in cohos and 124 to 209 in chinooks. The fish Rudisil brought to the DEC office had a pyloric caeca count in the 94-100 range.

“We counted it three times,” Bishop said. “It’s clearly right in between a coho and a chinook.”

In addition, the fish's caudal fin had typical characteristics of a chinook and an anal fin typical of a coho, said David Lemon, the DEC's Regional fisheries manager.

"Clearly, no doubt about it being a hybrid," he said.

Bishop said crossbred salmon are unusual but do pop up in Lake Ontario and its tributaries, such as the Salmon River, from time to time.

“It could have occurred naturally, or accidentally at the DEC hatchery,” he said.

The world record for a coho-chinook hybrid is 35 pounds, 8 ounces, pulled out of the Salmon River on Oct. 21, 2001, by Brooks Gerli, according to a spokesman from the International Game Fish Association.

“We got knocked out of the box, both ways,” Buffa said. “Either way, it was an exciting adventure and a beautiful fish.